drm/i915: Wrap engine->schedule in RCU locks for set-wedge protection

Similar to the staging around handling of engine->submit_request, we
need to stop adding to the execlists->queue prior to calling
engine->cancel_requests. cancel_requests will move requests from the
queue onto the timeline, so if we add a request onto the queue after that
point, it will be lost.

Fixes: af7a8ffad9 ("drm/i915: Use rcu instead of stop_machine in set_wedged")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180307134226.25492-5-chris@chris-wilson.co.uk
(cherry picked from commit 47650db02d)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
This commit is contained in:
Chris Wilson 2018-03-07 13:42:25 +00:00 committed by Joonas Lahtinen
parent 84d4ebdb6c
commit 7e9d3a4a1b
2 changed files with 9 additions and 6 deletions

View File

@ -471,10 +471,11 @@ static void __fence_set_priority(struct dma_fence *fence, int prio)
rq = to_request(fence);
engine = rq->engine;
if (!engine->schedule)
return;
engine->schedule(rq, prio);
rcu_read_lock();
if (engine->schedule)
engine->schedule(rq, prio);
rcu_read_unlock();
}
static void fence_set_priority(struct dma_fence *fence, int prio)
@ -3214,8 +3215,11 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
*/
for_each_engine(engine, i915, id) {
i915_gem_reset_prepare_engine(engine);
engine->submit_request = nop_submit_request;
engine->schedule = NULL;
}
i915->caps.scheduler = 0;
/*
* Make sure no one is running the old callback before we proceed with
@ -3233,11 +3237,8 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
* start to complete all requests.
*/
engine->submit_request = nop_complete_submit_request;
engine->schedule = NULL;
}
i915->caps.scheduler = 0;
/*
* Make sure no request can slip through without getting completed by
* either this call here to intel_engine_init_global_seqno, or the one

View File

@ -1081,8 +1081,10 @@ void __i915_request_add(struct i915_request *request, bool flush_caches)
* decide whether to preempt the entire chain so that it is ready to
* run at the earliest possible convenience.
*/
rcu_read_lock();
if (engine->schedule)
engine->schedule(request, request->ctx->priority);
rcu_read_unlock();
local_bh_disable();
i915_sw_fence_commit(&request->submit);